Number-indicating switch assembly



United States Patent 3,283,090 NUMBER-INDICATING SWITCH ASSEMBLY Donald C. Hausser, Chicago, and Raymond L. Meeder,

Palos Heights, 11]., assignors to Nuclear-Chicago Corporation, Des Plaines, Ill., a corporation of Delaware Filed Apr. 15, 1953, Ser. No. 272,965 14 Claims. (Cl. 200-18) This invention relates to a device for decimal number indication of mechanical position, and more particularly to a switching device adapted to be connected to a multiposition mechanical system to connect appropriate electrical circuits for visual display or print-out of decimal digital position information concerning a mechanism mechanically coupled .to the transducer or number generator.

A variety of types of switching systems for the general purpose mentioned above are known. One example is the odometer-type switch wherein structures closely analogous to those of an odometer used for revolution counting, etc., are provided with suitable stationary and movable contacts for each digital order (units, tens, hundreds, etc.) indicator of the odometer. An ordinary odometer has a capacity (maximum indication) of a number equal to a power of ten (100, 1000, etc.) determined by the number of digital 0 through 9 indicators (normally Wheels) in the set. The number indications, whether used with or without electrical switching provision, are .mechanically coupled by various forms of intermittent motion couplings or gearing normally producing one discrete position advance of each higher-order digit wheel for each full revolution of the preceding or lower-order wheel, the position advance occurring as the previous wheel goes from 9 to 0 in preparation for a new cycle.

Odometers and odometer switches may readily be employed as position indicators for various forms of mechanical systems. In the embodiment of the invention to be presently described, the invention is used in a system for the counting or measurement of radioactive samples, wherein the samples are disposed on an endless conveyor which delivers them to the counting station. Such systems are used in automatic data-taking in laboratories, etc., and normally incorporate, as part of the system, a print-out device displaying on a tape, or on cards, etc., the recorded data, along with the sample number, i.e., the number of the conveyor receptacle by which the sample is identified for this purpose. For this and similar purposes, a conventional odometer switching device can frequently be used fully satisfactorily as, for example, where there are 100 sample positions on the conveyor, sequentially numbered; by simply gearing the conveyor drive to the odometer-type switch, in a manner appropriate to produce advancement of the numerical indication by one digit with each advancement of a sample position, the position indication may readily be transmitted to the print-out device, ordinary stock-type odometer switches thus being suitable for the purpose of sample number generation. Continuous recycling of the equipment, or even reversal of direction (with most constructions), does not interfere with the proper number indication.

Where such a mechanical system has a total number of positions to be indicated other than powers of 10, such as 50 or 200, for example, some modification of conventional odometer-type devices is required. Thus a system having 50 positions requires modification of the tens switch of a conventional two-digit construction by, for example, providing only five digits (and five sequential positions) of the tens switch, so that instead of proceeding to 99 and then recycling, the switch proceeds to 3,283,090- Patented Nov. 1, 1966 49 and then recycles. Similarly, to produce proper direct indication of 200 positions of an endless system, a three-digit odometer-type switch may be employed, with only the highest-order digit switch modified to display only two possible digits (0 and I). It will be noted that in either of these examples, if the direct visual indication of an ordinary odometer is not used (or is not inscribed on the number generator), the entire mechanism may readily be employed in its original form merely by making proper connections of the contacts of the highest-order ten-position switch section.

The present invention lies in this general type of switching arrangement, i.e., a switch for the same general purposes as the odometer switches just discussed, as applied to position indication in endless systems. The possibility of simple utilization of odometer switches disappears when the total capacity to be registered is represented by a number which is other than 0 in a digit of other than the highest order. In the embodiment of the invention to be described, the device of the invention is used with an endless conveyor having sample receptacles. It will be seen that with this type of number, drastic revision is required of any odometer system. The difliculty, of course, stems from the fact that in a case such as that mentioned, the first cycle of the tens indication goes all the way to 9 before recycling to 0, while in the second cycle, the return to 0 is made from the number 4 (i.e., the highest number being 149, with the all-zero indication following).

It is of course possible to solve such a problem by employing (in the example mentioned above and to be specifically treated throughout, although merely exemplary) fifteen positions of the second digit switch, the first ten being connected to switch in the indications 0 through 9 and the last five 0 through 4, with appropriate provision for advancing the highest order digit from 0 to 1, and reverse, at each progression of the tens to 0. However, there is now introduced the great complexity of a fifteen-position switch, creating difliculties in procurement in addition to inherent uncertainties of indexing, close mechanical tolerances, etc.

It is therefore the principal object of the present invention to provide a position indicator structure for this purpose capable of being manufactured with economy comparable to that of an ordinary fully decimal system.

As previously indicated, the example to be described herein of use of the invention will be that of indication of a full capacity of 150, but the application to other numbers containing the digit 5 (and also 2) in a place other than the highest decimal order will be readily apparent.

The invention will be readily understood by reference to the description given below of the embodiment illustrated in the drawing, in which:

FIGURE l is a highly schematic mechanical and electrical diagram illustrating the device of the invention;

FIGURE 2 is a view in elevation of a particularly advantageous embodiment of a portion of the device illustrated schematically in FIGURE 1, and

FIGURE 3 is a fragmentary view in elevation of a portion of the device of FIGURE 2, as indicated by the line 3-3 in that figure.

As seen in FIGURE 1, the mechanical input to the switching device illustrated is by geared connection to a ISO-position endless conveyor, such as the conveyor for use in the measurement of liquid scintillation radioactive samples described in the co-pending application of Meeder and Kus, Serial No. 273,067, filed .April 15, 1963, the device illustrated in the present drawing being designed for accurate indication of the identification of each sample counted. The input to the device of FIGURE 1 is through a gear schematically shown at 12, coupled to a gear 14 to which is secured (as indicated by dotted 'mittent nature well known in the art, the schematic representation of the single tooth 26 indicating any well known construction for this purpose, as is also true in similar representations following. Likewise, it will of course be understood that the representation of the coupling 22 can include any desired construction. As

indicated, however, the overall coupling between the gear 14 and the gear 24 is such as to produce one revolution of the gear 24 for each ten revolutions of the gear 14. -As shown by dotted lines 25, the gear 24 is directly coupled to the rotor 28 of a switch 30 and the rotor 32 each having to 9 positions, connected to a set of output leads 35, but the rotor 32 being five positions ahead of (or behind) the rotor 28. 4

As shown by a further dotted coupling 36, the gear 24 is coupled to a gear 38, the intermittent nature of this coupling again being shown by the schematically indicated single tooth 39. The gear 38, as shown by the dotted line coupling 40, bears the rotor 42 of a 3-position switch 44, having two 0 contacts and a 1 contact, as shown by the connections to the output lines 45. The intermittent motion teeth 39 in this instance represent an indication that the switch 44 is moved one position .each time that the previous switch reaches 0 or 5; it will be noted that the opposite phasing of the rotors of the switches 30 and 34 creates an apparent ambiguity as to which of the latter is occurring, but it will be observed below that this mechanical ambiguity is made irrelevant by the electrical and mechanical coupling. The overall gear ratio between the gears 24 and 38 is such that the showing of the drawings, makes one revolution for each one and one-half revolutions of the gear 24, so that the overall effect is that the rotor 42 is moved through one switch position each time that either of the rotors 28 or 32 goes from 9 to O.

The gear 38, in the schematic illustration of FIGURE 1, is, as shown by dotted coupling 46, coupled to a 2- position (single pole double throw) switch 48 of which 'the stationary contacts are connected to the respective rotors 28 and 32 of the switches 30 and 34.

In this case, the intermittent drive representation tooth at 50 again indicates advancement of the switch 48 by one position on each revolution of the gear 38, but since the entire cycle of the switch 48 consists of only two positions, the net effect is merely reversal of the position of the switch 48 with each full cycle of the switch 44.

The operation of the system of FIGURE 1 may be readily understood from what has already been said about the purpose of the device, coupled with the description of the structure. The switch 20 is of course the units switch,

' the switch 30 or 34, depending upon the position of the switch 48, is the tens switch, and the switch 44 is the hundreds switch. The switches are illustrated as connected for indication of the 000 or reference position of the conveyor. As will be obvious, the operation as the conveyor is moved through the first'49 samples will be confined to the switches 34 anl 20, operating in the same manner as a conventional odometer-type switch. As the number 50 is reached, the switch 44 goes to the second 0 position, but the operation still remains that of a conventional odometer switch otherwise. As the conveyor goes from position 99 to position 100, the rotor 42 moves to the 1 position, again as in a convention-a1 type of arrangement, and then again ordinary odometer switch operation of the two lower orders is restored. As the conveyor goes from position 149 back to the reference posiof a switch 34, these being identical l0-position switches latter, as indicated by the gear ratio legend and schematic v the same result.

30 and 34, is likewise completely conventional.

- special construction best seen in FIGURE 3.

tion, however, the switch 48 is reversed, thus now making the switch 30, rather than the switch 34, active as the tens switch. The switch 44 has now returned to its reference position, so that in the next cycle of the conveyor, the operation is exactly the same as previously described except that the switch 30 is substituted for the switch 34. After the completion of the second cycle of the conveyor, the entire operation returns to the original condition first described.

The practical construction of the system schematically illustrated in FIGURE 1 is simple and inexpensive as compared with any other known system for producing The units switch is of course completely convention-a1 both in its construction and in its manner of input and output mechanical coupling. The tens switch, when considering either of the two portions The two portions 30 and 34 may be constructed in a number of simple ways. For example, if a simple wafer-type rotary switch is used, the two portions 30 and 34 may be merely separate wafers. Itwill be observed that although the schematic diagram shows the rotors 28 and 32 in differing mechanical phase, actually the mechanical construction may use two gangs in the same phase, with the connections to the output lines 35 producing the actual phase differential. Conversely, although the schematic diagram shows the two switches 30 and 34 with separate sets of contacts, the interconnections illustrated, both mechanical and electrical, make this entire assembly of two switches as illustrated actually a single switch having two mutually insulated rotors, and such a construction may in fact be used.

The hundreds portion of the system likewise may assume a large variety of forms of detailed construction. For example, it will readily be observed that the representation of the switch 44 as a 3-position switch is highly schematic as regards the actual requirements, and any switch having a number of positions which is an integral multiple of three can be used, or, as in a detailed construction shortly to be described, this switch may merely be replaced by a camming system with a simple 2-position switch. Likewise, the coupling 46 and switch 48 may take a similar large variety of forms.

In FIGURES 2 and 3 is shown a simple mechanical construction advantageously used in the hundreds portion of the arrangement of FIGURE 1. As there shown, a microswitch 52 having a roller type actuator arm 54 operating a plunger is coupled to a cam 58 on a shaft 60 (this being the shaft of the gear 38 of FIGURE 1 of which the construction details are conventional and not here illustrated). The cam 58 has a smaller diameter portion 62 extending through two-thirds of its circumference, and an enlarged diameter switch-actuating portion '64 extending over the balance. The cam is shown in the reference or 000 position. This assembly is designated as 44a in the drawing, to indicate that it is a mechanical construction of the switch 44 of FIGURE 1.

60 to the switch 48, corresponding to the dotted coupling 46 of FIGURE 1, is performed by the novel assembly designated as 46a in the drawing. The shaft 60 bears a single tooth 50a (which is of course mounted on the shaft 60 behind the cam 58) engaging a gear 72 of a The gear 72 is an eight-tooth gear with alternate teeth 74 milled partially off, and the other alternate teeth 76 left intact 80 and the actuating arm 68 of the switch engages the four-tooth portion 78. A detent 82 in the form of an a-rm-and-roller assembly substantially identical. to that of the actuator arm 68, for convenience of construction, also engages the eight-tooth portion 80, defining eight rotary positions, in four of which the switch 66 is actuated by the teeth 76. The condition of the switch 66 is thus alternated in each cycle of rotation of the shaft 60.

Upon study of the illustrated embodiment of the invention, it will be seen that the underlying principle of operation of the device schematically illustrated in FIGURE 1 .may be applied in a large variety of Ways, wherever recycling numerical .indication of decimal position indications is required with total capacities having a digital order .lower than 0 in a digit other than the highest power of 10. As an obvious example, the principle may be easily adapted .to cases where the units digit of the maximum capacity is other than 0. Furthermore, although the construction illustrated is particularly advantageous where the digit creating the problem is 5, because of the simplicity of the illustrated solution to the problem, the general principle may be extrapolated to other numbers. For example, a maximum capacity of 120 may be constructed by substituting for the present two-rotor construction of the tens switch a five-rotor construction (which may again use Wholly or partially identical or duplicative number digit contacts) with appropriate substitution of a S-position switch for the switch 48 and similar alteration of the switch 44 (whether a tap switch or a cam), with the gear ratio between the gears 24 and 38 in this instance, of course, being 1.2 instead of the 1.5 presently illustrated. Other numbers creating such a problem can likewise be made to be the recycling point or maximum indication by the addition of slightly more complexity, as required where the non-zero digit is not an integral submultiple of '10. In such cases, depending upon the particular value,

all or a part of the proper synchronization may be obtained by the mere addition of further rotors, with appropriate modification of the rotor activating switch corresponding to 48, or by introducing other factors such as double or triple position-advancing producing rotary motion of a single switch in a manner such that in successive cycles its connections are not identical by reason of the :fact that it has a number of positions which is not an switching in, with each successive overall cycle, of the tap contact which lags the one just previously in use by the number of positions corresponding to the non-zero Value of the digit in the total number of positions which must the cyclically indicated.

It will also be observed that the assembly of FIGURES 2 and 3, and particularly the manner of coupling the tooth 50a to produce alternating actuation of the switch 66, will find other utilizations than that herein described.

Accordingly, the scope of the protection to be given the invention should not be limited to the particular embodiments herein illustrated, but should extend to all structures described in the appended claims, and equivalents thereof.

What is claimed is:

1. A position-indicating switch assembly for recycling successive indication of a total number of positions having a non-zero digit in a decimal order other than the highest order, comprising (a) a highest order digit switch and gear means for cycling this switch,

(b) ten-position rotary switching means having 0 through 9 contacts and a plurality of wiper contacts each successively contacting the 0 through 9 contacts in the ten positions but successively spaced in rotational phase by the number of positions equal to said non-zero digit,

(c) said ten-position switching means being driven by a gear comprising a portion of said gear means at a cycling rate which is a numerical and fractional of decimal numbers up to a maximum having a non-zero multiple of the cycling rate of the highest-order switch corresponding to said total number of positions,

((1) and switching means operable by the highest-order cycling means at the end of each full cycle of its operation to activate the wiper contact so succeeding the one activated during such cycle of operation.

2. The position-indicating switch assembly of claim 1 wherein the non-zero digit is 5, having two wiper contacts in phase opposition and a switch mechanically coupled to the gear means and alternating the activation of the respective wiper contacts at the conclusion of each full cycle of the highest-order switch.

3. The switch assembly of claim 2 wherein the gear means includes a cam cycling the highest-order switch, said cam having on the same shaft an intermittent actuation means operating the alternating switch.

4. The switch assembly of claim 2 wherein the mechanical coupling of the alternating switch to the gear means includes a unitary gear having on one portion an even number of teeth and on another portion only alternate ones of said teeth, the switch being actuated by the latter portion, and the gear being rotated through the angle of one tooth of the former portion in each cycle of the highest-order switch.

5. A gear-actuated alternating-condition switch assembly comprising urged roller apart from the actuator seated on said first portion of the gear.

7. A switch assembly for recycled electrical indication digit other than the digit of highest order comprising (a) a lower-order digit indicator comprising-a switch having ten mechanical positions and means to cycle the switch through successive positions,

(b) a highest-order digit indicator comprising a switch having states corresponding to values of the highest order digit to be .indicated, and means to cycle the highest-order switch through its states,

(c) said last cycling means coupling the lower-order switch to the highest-order switch for cycling of the latter through its states in the number and fraction of cycles of the lower-order switch corresponding to the maximum number to be indicated,

((1) the lower-order digit indicator having 0 to 9 indicator output-s cyclically energized in response to change of switch position to form an indication cycle,

(e) means to select one of a plurality of relative phases between the position cycle of the lower-order switch and the indication cycle thereof,

(f) and means to actuate the phase-selecting means on each completion of the cycle of the highest-order indicator to alter said relative phase in the lowerorder switch to set the lower-order output indicator to 0.

8. The switch assembly of claim 7 wherein the non-zero digit is a sub-multiple of 10, the number of selectable relative phases between position and indication being the other sub-multiple.

9. The switch assembly of claim 7 wherein the non-zero digit is 5, the phase-selecting means comprising a switch reversing the relative phase of position and indication of the lower-order indicator on each actuation of said reversing switch.

10. The switch assembly of claim 9 wherein the reversing switch comprises a double-pole switch having an ,actu-ator member, the phase-selecting means comprising a rotary gear member having a gear portion and a switch actuation portion, the latter having half the number of teeth of the former, the actuator member on the switch abutting against the actuation portion, and intermittent drive means to rotate the gear member through an angle corresponding to one tooth of the gear portion upon each completion of the cycle of the highest-order switch.

11. The switch assembly of claim 7 wherein the phaseselecting means comprises a plurality of mutually insulated wipers on the lower-order switch and further switching means coupled to the highest-order switch and operable on each completion of a full cycle thereof to selectively connect said wipers.

12. A switch assembly for recycled electrical indication of decimal number identifications of an input condition up to a maximum number having a non-zero digit other than the digit of highest order comprising (a) a lower-order digit indicator comprising a switch having ten mechanical positions and input gear meansresponsive to an input drive to cycle the switch through successive positions,

(b) a highest-order digit indicator comprising a switch having states corresponding to values of the highestorder digit to be indicated, and intermittent gear means coupling the highest-order switch to the lowerorder switch to cycle the states of the highest-order switch,

(c) said intermittent gear means coupling the lowerorder switch to the highest-order switch for cycling of the latter through its states in the number and traction of cycles of the lower-order switch corresponding to said maximum number to be indicated,

(d) the lower-order digit indicator having to 9 indicator outputs energized in response to change of 7 switch position to form an indication cycle,

(e) means to select one of a plurality of relative phases between the position cycle of the lower-order switch and the indication cycle thereof,

(f) and means to actuate the phase-selecting means on each completion of the cycle of the highest-order indicator to alter said relative phase in the lowerorder switch to set the lower-order output indicator to 0.

13. A switch assembly for recycled electrical indication of decimal number identifications of an input condition up to a maximum number having a non-zero digit other than the digit of highest order comprising (a) a lower-order digit indicator comprising a switch having ten mechanical positions and means responsive to the input condition to cycle the switch through successive positions, (b) a highest-order digit indicator comprising a switch having states corresponding to all values of the highest-order digit to be indicated, and means for:

coupling the highest-order switch to the lower-order switch to cycle the states of the highest-order switch, (c) said last cycling means coupling the lower-order switch to the highest-order switch for cycling of the latter through its states in the number and fraction of cycles of the former occurring in reaching said maximum number,

(d) the lower-order digit indicator having 0 to 9 indicator outputs sequentially energized in response to change of switch position toform an indication cycle,

(e) means to select one of a plurality of relative phases between the position cycle of the lower-order switch and the indication cycle thereof,

(f) and means to actuate the phase-selecting means on each completion of the cycle of the highest-order indicator to alter said relative phase in the lowerorder switch to set the lower-order output indicator to O.

i 14. A switch assembly for recycled electrical indication of numbers representative of powers of a number base up to a maximum number having a non-zero digit other than the digit of highest order comprising (a) a lower-order digit indicator comprising a switch having positions equal in number to the number base and means to cycle the switch through successive positions,

(b) a highest-order digit indicator comprising a switch having states corresponding to values of the highestorder digit to be indicated, and means to cycle the highest-order switch through its states,

(c) said last cycling means coupling the lower-order switch to the highest-order switch for cycling of the latter through its states in the number and fraction of cycles of the lower-order switch corresponding to the maximum number to be indicated,

(d) the lower-order digit indicator having indicator outputs of 0 to one less than the number base cyclically energized in response to change of switch position to form an indication cycle.

(e) means to select one of a plurality of relative phases between the position cycle of the lower-order switch and, the indication cycle thereof,

(f) and means to actuate the phase-selecting means on each completion of the cycle of the highest-order indicator to alter said relative phase in the lowerorder switch to set the lower-order output indicato References Cited by theExaminer UNITED STATES PATENTS 1,965,092 7/1934 Zenkner 200-17 2,445,558 7/1948 Boisseau 200l8 2,661,401 12/1953 Joche'm et al. 200-18 2,737,548 3/1956 Mead 200153 2,963,628 12/ 1960 Ostland 200-38 FOREIGN PATENTS 776,572 6/ 1957 Great Britain.

OTHER REFERENCES German application 1,086,791, Aug. 11, 1960.

ROBERT K. SCHAEFER, Primary Examiner.

BERNARD A. GILHEANY, Examiner. J. R. SCOTT, Assistant-Examiner. 

5. A GEAR-ACTUATED ALTERNATING-CONDITION SWITCH ASSEMBLY COMPRISING (A) A SWITCH HAVING A RECIPROCATING ACTUATOR, (B) A GEAR HAVING A FIRST PORTION WITH AN EVEN NUMBER OF TEETH AND A SECOND PORTION WITH ONLY ALTERNATE MEMBERS OF SAID TEETH, (C) AND INTERMITTENT DRIVE MEANS REPEATEDLY ENGAGING THE FIRST PORTION TO ROTATE IT THROUGH AN ANGLE CORRESPONDING TO ONE TOOTH THEREOF, (D) THE ACTUATOR BEING IN CONTACT WITH THE SECOND PORTION FOR OPERATION OF THE SWITCH. 